Front-wheel suspension



Sept. 5,y 1950 J. H. BOOTH 2,521,335

' FRONT WHEEL SUSPENSION Filed oct. 24, 1947 y@ '/xmmv Patented sept. s,195o UNITED STATES `PATENT OFFICE f FRONT-WHEEL SUSPENSION James H.Booth, Corunna, Venice Township,

Shiawassec County, Mich., assgnor to Thompson Products, Inc., Cleveland,Ohio, a corporation of Ohio 'Application October 24, 1947, Serial No.781,996

This invention relates to independent wheel suspension apparatus forautomobiles. More particularly, -this invention relates to independentwheel suspension apparatus wherein ball joints are used at the outer endof the lower and upper control arms to accommodate knee action andsteering movement.

In front wheel suspensions of the type to which this invention relates,the thrust load due to the weight of the vehicle is carried by a lowercontrol arm supported from the vehicle frame through a spring while theshock load due to operation on uneven surfaces or the like is taken careof by the upper control arm acting through a shock absorber. Both ofthese arms are usually connected through a knuckle support to a steeringknuckle pivotally mounted on a pin which permits the wheel to be pivotedabout the king pin.

This invenon provides an eillcient arrangement of ball joints on theends of the wheel suspension control arms which, in connection with asteering knuckle, aiord independent wheel suspension action and easysteering of the front Awheels, and eliminates heretofore requiredknuckle supports, king pins, king pin thrust bearL ings, and king pinbushings.

The ball joint of this invention located at the outer end of the lowercontrol arm is designed to carry the combined thrust load due tobraking' and due to the weight of the automobile through a sphericalbearing surface to an antifriction bearing. Suspension movement of thewheel is accommodated by the spherical bearing and the radial steeringmovement is accommodated by the anti-friction bearing.

The ball joint at the outer end of the upper control arm is particularlyadapted to dampen vibrations and absorb shock loads by means of aresilient bearing member while permitting pivoting of the control arm ina substantially vertical plane and rotation of the steering member in ahorizontal plane.

This novel arrangement of a load carrying ball joint and a shockabsorbing ball joint in a wheel suspension device eillciently eliminatesshimmy and vibrations in the suspension system and affords easy,controllable steering of the wheels.

In one form of the shock absorbing ball joint, a. rubber dampener'with aplastic contact surface is used, while in a modiiied form a bronze wearplate is employed on the thrust surfaces.

It is therefore an object of this invention to provide, in anindependent wheel suspension, an eliicient arrangement of ball jointsfor absorbing vibrations and shock loads in the suspension and providingeasy steering of the wheels.

4 Claims. (Cl. 28o-96.2)

Another object of this invention is to provide a bearing which willeffectively carry the thrust load transmitted through the lower controlarm of an independent wheel suspension and will afford, through ananti-friction member. easy A steering characteristics.

A further object of this invention is to provide a bearing which, incooperation with the upper control arm of an independent wheelsuspension, will dampen vibrations in the system and still permitpivoting of the steering member.

Other and further objects of this invention will be apparent to thoseskilled in the art from the following detailed description of theannexed sheet of drawings, which illustrate one embodiment of theinvention.

On the drawings:

Figure 1 is a fragmentary vertical sectional view, partly broken away,of a portion of the front wheel suspension device of this invention.

Figure 2 is an enlarged fragmentary sectional view showing a modifiedform of the upperball joint used in a front wheel suspension of thisinvention.

As shown on the drawings:

In Figure 1, a right front wheel suspension arrangement is illustratedas viewed from the .rear of the car. It is believed that the inventionwill be adequately understood when described in connection with theright side of the front wheel suspension system, although it will, ofcourse, be recognized that the complete system includes an identicalsuspension device, oppositely dispnsed, at the left side of the vehicle.

Reference numeral I0 designates the brake drum of a. typical road wheelrotatably `mounted in the conventional manner on a wheel spindle I I.The spindle I I is preferably formed integral with a steering knuckle I2which is supported for swinging, steering movement at its upper andlower ends in ball joints I4 and I5, respectively. Steering movementofthe steering knuckle I2 1s accomplished through a rearwardly extendingsteering arm I3 which is controlled from the driver's seat through theconventional tie rod and drag link. j

The upper ball joint I4 is arranged to permit swinging of the knuckle I2and at the same time is adapted to accommodate pivoting in asubstantially vertical plane of an upper control arm II. Control arm I6includes a box-like housing IBa on its outer end in which the ball endIla of a stud member Il is seated, and an inner yoke arm I6b whichstraddles a shock absorber I9, the arms of the yoke being attached toopposite ends of the rotatably operating shaft 20 of the shock ab-2,5z1,335 l r sorber. A plurality of bolts 2| secure the shock absorberto a cross frame member 22 of the vehicle. A resilient member 23 issecured to an outer portion of the frame 22 directly below the uppercontrol arm I8 to limit the downward pivoting movement of the arm. Thestud I1 has a tapered shank portion wedged in a hole in the toll o! theknuckle I2 by means of a nut threaded on the end of the stud.

The lower ball joint I8 is arranged to accommodate the swinging andsteering movement of a stud 28 which has a tapered portion wedged in ahole in the bottom of the knuckle I2 by a nut 21 threaded on the end ofthe stud. The joint I8 also permits pivoting in a substantially verticalplane of a box-like housing end portion 28a of a lower control arm 28.At its inner end the arm 28 has a pair of arms 28h and 28e whichstraddle a downwardly extending portion 22a of the frame 22 beingconnected at either end to a pivot pin 88 which extends therethrough.Upper pivoting movement of the control arm 28 is resisted by a coilspring 3| which has its lower end disposed in an annular groove portion28d of a spring seat 28e attached to the arm 28 and its upper end guidedabout a downwardly projecting cylindrical portion 22h of the frame 22. Aresilient bumper member 33 secured to the spring seat 28e is arranged tocontact a projection 22e of the frame 22 to limit upward movement of thearm 28.

As previously mentioned, the lower ball joint I8 must carry the load dueto the weight of the automobile and must, at the same time. provide foreasy steering of the road wheel. The housing 28a of the joint I8 has anopen bottom closed by a cap member 38 which is secured in the housing bypeening or spinning a shoulder from the end of the housing under a rimilange 88a of the cap. A spring 31 is disposed between the bottom wallof the closure member 88 and a retainer 88, which has an upper sphericalsurface arranged to receive the lower spherical end of the stud 28.

Ease of steering is provided by separate sets of anti-friction bearingsincluding a plurality of needle bearings 48 which are disposed aroundthe stud 28 inside a central aperture of a substantially semi-sphericalshaped bearing member 42 and a roller or ball bearing assembly 44 whichis Y positioned about the extreme lower end of the stud 28. Thisassembly 44 includes an upper race 44a disposed in a recess in the lowersurface of the semi-spherical member 42 and a lower race 44h abutting ashoulder portion 28a of the lower end of the stud 28. The semi-sphericalbearing 42 is adapted to swing or tilt in a' mating spherical socket inthe box-like end 28a of the lower control arm 28. Thus the anti-frictionbearings 48 and 44 permit easy rotation of the stud 28 about its ownaxis. The roller bearing assembly 44 takes the vertical thrust loadstransmitted from the stud 28 through the semi-spherical bearing 42 tothe socket 28a and arm 28.

To prevent dirt from entering the ball joint' a pair of closure washers48 with a felt washer 41 therebetween is disposed about the stud 28 overthe top opening in the housing 28a through which the stud 28 projects. Acoil spring 48 is also disposed about the stud 28 between the top washermember 48 and the steering knuckles I2 to urge the washers 48 intosealing positions.

The upper ball joint I4 of this. invention is designed to dampenvibration in the system and to permit pivoting of the steering knuckleI2. This ball joint comprises the outer box-like end portion Ila of theupper control arm I8, which end portion has a central cylindrical cavity88 in which is arranged the ball end I1a of the integral ball and studmember I1. The lower half of the ball l1a is enclosed by a metal bearingring 8I which has,.an outer marginal portion that lits snugly in thecavity 88, and an inner segmental spherical socket portion adapted toreceive the ball I1a. The upper end portion of the ball I1a is enclosedby a bearing ring 82 which has an outer member 84 made of resilientmaterial such as rubber and adapted to be positioned in the cavity 88directly above the lower bearing member 8|. The resilient member 84 hasan inner spherical socket to which is secured a wear resistant plasticliner or plain bearing member 88, of spherical shape and adapted toreceive the top half of the ball I1a. Lubricant is fed into the housingfrom an oil tting 81 which is secured to a top closure plate 88 spuninto the open top of the housing I8a.

The lower end of the ball joint I4 is sealed against the entry of dirtby a plurality of washers 88 including an intermediate felt washerdisposed about the stud I1 and held against the lower end of the jointby a spring 8l.

The ball joint I4 thus provides plain bearing surfaces for accommodatingtilting and rotating movements of the stud I1. Further, since one f thebearing surfaces is backed by a loaded resilient element 84 the jointwill absorb and dampen out vibrations.

In Figure 2, a modification of the upper vibration-absorbing ball jointis illustrated. The boxlike end housing 84 of the arm I8 in thisembodiment has a central cavity 88, which lcavity has a spherical socketportion adapted to receive a substantially semi-spherical bearing member88. A stud 88 secured by wedging its tapered wall into a hole in thesteering knuckle I2 by a nut 88, projects through a central opening inthe bearing member 88 being journaled therein on a plurality of needlebearings 18. A substantially circular bronze wear plate 12, having acentral aperture, is disposed loosely about the stud 88 iltting in arecess portion 88a on the Vupper surface of the bearing member 88. Anupper collar portion 88a of the stud 88 is arranged to bear down on theupper surface of the bronze wear plate 12. Thus, should the wheel fallinto a hole, a sudden shock load will be transmitted from the steeringknuckle and the stud 88 through the bronze wear plate 12 and thespherical bearing 88 to the Vsocket I8a and arm I8.

The modified joint shown in Figure 2 is enclosed at its bottom portionagainst the entry of dirt and dust by a plurality of washer members 14which are held against the surface by means of a spring 18 disposedbetween the washers and the steering member I2.

The upper end portion 88a of the stud 88 has a spherical contour fittinginto a spherical retainer socket member 11 which is resiliently held inspaced relation from an upper closure plate 19 by means of a coil spring18.

Thus, this modified ball joint is arranged to permit rotation andtilting ofA the steering knuckle stud 88. The rotation is borne byantifriction bearings but the plain thrust bearing provided by thespring loaded bronze wear plate will be effective to continuously dampenout vibrations, and also to absorb the shock load incident to suchvibrations. The vibration control is directly iniluenced by the load ofspring 18 and adjustments of spring loads will effect desired dampeningcharacteristics.

From the foregoing description it is seen that this invention providesindependent wheel suspension apparatus which does away with many of thestandard conventional items such as king pins, knuckle supports, andking pin bearings and affords easy steering characteristics for thesteering mechanism and adequate pivoting facilities for the knee actionapparatus. The load on this suspension device due to braking action anddue to the weight of the vehicle is adequately carried by a lower balltype anti-friction point while shock, braking loads and vibrations inthe system are `absorbed by loaded plain thrust bearings disposed in theupper ball joint.

It will, of course, be understood that various details of Vconstructionmay be varied through a wide range without departing from the principlesof this invention and it is, therefore, not the purpose to limit thepatent granted hereon otherwise than necessitated by the scope of theappended claims.

I claim as my invention: v

1. In an independent steerable wheel suspension including a pivotallymounted load carrying wheel arm, a pivotally mounted second wheel arm, aWheel knuckle, and ball joints each including a headed stud and aninternal bearing wall equipped socket connecting the wheel knuckle andarms to accommodate pivoting suspension action of the arms and rotatingsteering movement of the knuckle, the improvements of a bearing ringhaving an external bearing wall tiltable on the bearing wall of thesocket for the load carrying arm and accommodating pivoting wheelsuspension action and rotatably carrying the stud therein, the head ofsaid stud and ring having opposed suspension load carrying surfaces,anti-friction elements between said surfaces accommodating free relativerotating movements of the stud and ring to facilitate rotating steeringmovement of the knuckle, said stud and socket of the joint .for thesecond arm being provided with opposed bearing surfaces accommodatingpivoting wheel suspension action and rotating steering action of thestud and socket, means defining a plain bearing surface in said socketfor the second arm acting on the stud head therein to impart a,predetermined resistance to rotating steering action of the knuckle, andmeans in the socket resiliently urging said plain bearing surfaceagainst the stud head to develop a friction force for dampening outvibration tending to rotate the knuckle.

2. In an independent steerable wheel suspension including a pivotallymounted load carrying wheel arm, and a pivotally mounted second wheelarm, a wheel knuckle, and ball joints each including a headed stud andan internal bearing wall equipped socket connecting the wheel knuckleand arms to accommodate pivoting suspension action of the arms androtating-steering movement of the knuckle, the improvements of a bearingring in each socket having an external bearing wall tiltable on thebearing wall of each socket and accommodating pivoting wheel suspensionaction and rotatably carrying the headed stud of each joint, each studhead and ring being provided with opposed surfaces, anti-frictionelements between said opposed surfaces ln the ball joint for the loadcarrying wheel arm accommodating free relative rotating movements of thestud and ring to facilitate steering rotation of the knuckle, andsprint: means loading the opposed surfaces in the ball point for thesecond arm to urge the surfaces together for developing a friction forceto dampen' out vibration tending to rotate the knuckle.

3. In an independent steerable wheel suspension including a lower loadcarrying wheel arm, an upper wheel arm, a wheel knuckle, and ball jointseach including a headed stud and an internal bearing wall equippedsocket connecting the wheel knuckle and arms, said ball joint connectingthe load carrying wheel arm and knuckle having the stud thereof intension under the load on the arm, the improvements of a bearing ring ineach socket receiving the stud therethrough and having an externalbearing wall tiltable on the bearing wall of the socket for mounting thestud in the socket to accommodate suspension movement of the wheel arms,antifriction elements between the stud and bearing ring inthe lower balljoint for facilitating rotation of the stud in the ring to accommodatefree steering rotation of the knuckle, a plain bearing acting on thestud head in the upper ball joint, and'means resiliently urging theplain bearing r member into engagement with the stud head for creating afriction force to dampen out vibration tending to rotate the knuckle.

4. In a wheel suspension including upper and lower wheel carrying arms,a wheel knuckle, and upper4 and lower ball joints each including aheaded stud and an internal bearing wall equipped socket connecting thewheel knuckle and arms, spring means acting on one of said arms totransfer suspended load thereto, the ball joint connecting the loadedarm with the knuckle having a bearing ring rotatably surrounding thestud and provided with an external bearing wail tiltable on the bearingwall of the socket, antifriction load carrying elements between thebearing ringand stud facilitating relative rotation therebetween toimpart free steering action to the knuckle, the other ball joint havingplain bearing surfaces between the stud and socket thereof accommodatingsuspension action of the arms and steering action of the knuckle, afriction imparting member in the socket of said other ball joint actingon the head of the stud to resist rotation of the stud in the socket,and means resiliently loading said friction imparting member to create afriction force dampening out vibration tending to rotate the knuckle.

JAMES H. BOOTH.

REFERENCES CITED The following references are of record in the file ofthis patient:y

UNITED STATES PATENTS Alldredge Feb. 15, 1949

